The invention relates to the reproduction of a master or original such as, for example, a frame of exposed and developed color film.
More particularly, the invention relates to adjustment of an image of a master preparatory to reproduction.
An apparatus for the reproduction of a colored master may include a color monitor which is used to produce a color image of the master. An operator can then correct the density and color of the image prior to making a reproduction of the master.
Apparatus of this type are used mainly by professional photographers to make prints of color negatives. The image on the monitor is evaluated by an operator who then adjusts the color filters and the exposure times. The color negatives are scanned by means of light and the resulting data stored in analog form or digital form. The image on the monitor is produced using these data.
The German Auslegeschrift 27 19 821 discloses an apparatus in which a monochromatic frame is generated on the monitor screen around the color image. The color of the frame is the same as the basic color of the printing or copy paper to permit appropriate visual comparison upon evaluation of the image. However, it has been found that a reference surface which surrounds the color image is not satisfactory. Thus, as an example, there is too large a spacing between the reference surface and a zone to be evaluated when such zone lies in the middle of the color image.
The German patent 33 07 326 teaches an apparatus where a second reference surface, which can be shifted across the screen, is provided in addition to the reference frame. The second reference surface can be placed directly adjacent to the critical zone to be evaluated. However, since only a single, predetermined reference color is again available, evaluation remains difficult.